Triple-valve mechanism



Sept. 29, 1925.

w. F. ATwooD TRIPLE VALVE MECHANISM Filed oct. 27. 1924 4 Sheets-Sheet lSept 29, 1925. 1,555,619

w. F. ATWOOD TRIPLE VALVE MECHANISM Filed out. 2?. 1924 4 Sheets-Sheet 2Sept. 29, 1925. 1,555,519

w. F. ATWOOD TRIPLE VALVE MECHANISM Filed Oct. 27. 1924 4 Sheets-Sheet 4l-II } Z83 E Tia-.5.

Witmeoo Patented Sept. 29, 1925,

UNITED STATES PATENT WALTER F. A'rwoon, or AMARILLO', TEXAS.

TRIPLE VALVE MECHANI'fiM.

Application filed'October 27, 1924.

This inventionrelates to a triple valve,

mechanism,- and particularly to a constructioncomprising: an improvementupon my prior Patent No. 1,120,58l dated December 8, 1914, in which pro'ision was. made for aforcible release moveijnent of the triple pistonto assure its positive action upon an increase in train line pressure.

In this character of mechanism where the brakes are used upon a longtrain, it has been round necessary to increase the train line pressureatthe head of the train in order to overcome the pipeline resistance.

to the rear cars thereof andprovide suiiicieut pressure at the latterpoint to properly release the brakes. As a practical result the brakesare released upon'the forward cars ofthe train beforethe similar actionof the rear brakes, whichirpquently causes heating or gripping of therear brakes of the train, resulting in accidents.

.lt therefore becomes important to provide a pressure medium extraneousto the train line pressure and cooperating upon a slight increasethereinin order to forcibly initiate the releasing movement of all of thebrakes simultaneouslywithout requiring an excessive built up pressure atthe head of the train. Provision must also be made for compensating forany train line pressure at the train head, and for that purpose theauxiliary reservoir is arranged to be overcharged during a predeterminedperiod and this pressure later balanced in a second auniiiary reservoir,the latter being particularly designed for cooperation with the workingor control piston by which the release movement is initiated.

The invention has for an object to provide a novel and improvedconstruction of the triple valve mechanism comprising a pluralityauxiliary cylinders adapted to be controlled by the movement of thetriple piston to act jointly or independently either upon the brakecylinder or upon the controlling means for releasing the triple piston.

Serial No. *746,211.

A further object of; the invention is to provide a construction inwhichthe triple piston is adapted to be forcibly released by a mechanicaldevicerupon an increaselni the train line pressurethrough the mediumrof.

an independent pressure-supply foractuat 111g said mechanical device 1nconjunction with the traineline pressurewhich under this arrangementneed only be increased tota small extent as it is supplemented bytheauxiliary reservoir pressure in .theareleasingaction.

A further objectrofitheinvention is-to provide a novel and improvedconstruction of triple valve and cooperating;graduating valve adapted tocontrol the'supp'ly froma plurality of auxiliary reservoirs to both thebrake cylinder and to a control chamber cooperating with the controlpiston The invention also has for an object to present an improvedconstruction OftllG-COIh trol chamber by which the auxiliary pres= sureis admitted to the control piston; the.

valve actuating member of; each chamber. being exposed to-the trai nline. pressure as balanced against the auxiliary pressures,

Other and further Ob eQts andi advantages of the invention Wlllbehereinafter set forth and the novel features .thereolwde fined by theappended claims.

In the drawings :i-

Figure 1 is'a longitudinalsection showing the parts in running position;

lligure 2 is a similarview with the parts in service or chargingposition;

l igure 3 isa' like view with; the. parts in position for "forciblerelease by cooperationof the control piston;

Figure 4 is an enlarged detail section-of the triple valve inrunningcposition';

Figure 5- is a bottom plan set the.graduating valve;

Figure 6 is top plan of thestriple slide valve;

Figure 7 is a bottom plan thereof;

Figure 8 is plan of the'valve seat;

Figure 9 is an enlarged detail section of the control valve; and

Figure 10 is a detail section of the governor connection between. theauxiliary reservoirs.

Like characters of reference designate corresponding parts throughouttheseveral views of the drawings.

The general construction and arrangement of the triple piston and itscooperating parts is as shown in my patent before mentioned, so thatthey will not be specifically described herein as the invention isdirected to the improvements in the applica tion of the auxiliarypressure to the triple piston.

The casing may be of any desired size or configuration, for instance ofthe usual standard in this art, and is provided with a cylinder Aadapted to receive the-triple piston 11 and an auxiliary chamber B intowhich the stem 12 of said piston extends. The movement of this stem in areleasing action is cushioned by means of a spring bumper 13 of anydesired construction. The casing is further formed with a chamber Cwhich communicates with the triple piston cylinder by ports 14 disposedin the partition 15 and at the opposite end of the chamber G a partition16 is provided from which a tubular cylinder 17 extends and issurrounded by a spring member 18 bearing upon a thimble 19 substantiallyas shown in my prior patent.

The casing is further provided with a control cylinder D adapted toreceive the control piston 20 from whicha stem 21 ex tends and isadapted at its free end 22 to contact with a block 23 carried by thetriple piston 11. The stem extends through the cylinder 17 and carries apiston member 24 provided with a valve 25 cooperating with a valve seat26 formed in the partition 16, these parts also operating as in myformer patent.

The casing 10 is also formed with a chamber E adapted to receive theemergency piston 27 and also the check valves 28 and 29 which operate inthe usual manner in this art upon an emergency application of thebrakes. From this emergency chamber a brake line pipe 30 extends to theusual brake cylinder while the casing is also pro vidcd with the trainline conduit F extending from the train pressure line 31 to the chamberC before described and gradually decreasing in area or dimensions aswill be hereinafter set forth.

I The auxiliary reservoir used in connection with this invention iscomposed of a primary reservoir 8- and a secondary reservoir H, theformer communicating by a line 32 with the auxiliary chamber B and thelat' ter by a line 33 with a conduit 34 extending to the valve seat uponwhich the slide valve I is mounted. This valve is actuated in the usualmanner by contact with shoulders 34 and 35 upon the stem 12 of thetriple piston 11 and comprises the main or triple valve. Cooperatingwith this valve is a graduating valve J which is secured to the stem 12and adapted to reciprocate upon the valve 1.

For the purpose of conducting pressure from the auxiliary chamber to thebrake line 30 a conduit 36 is formed in the casing and preferablyincreases in area from the valve seat to its outlet. The triple valve Iis formed with a port 37 extending therethrough and adapted tocommunicate with a conduit 36 for admitting pressure directly from theauxiliary chamber to the brake cylinder line. Cooperating with this port37 is a branched port 38 which when the parts are in the serviceposition shown in Figure 2 is adapted to communicate with a recess 39 inthe graduating valve J and this recess also communicates with a port 40extending through the valve I and adapted to establish communicationwith the conduit 34 communicating with the secondary auxiliary reservoirH. The ports 37 and 38 are preferably formed each of substantially onehalf the area of the conduit 36 as shown in Figure 4 for the purpose ofequalizing the pressure received from each of the auxiliary reservoirsas with the parts in service position pressure is transmitted to thebrake cylinder from the primary reservoir through the port 37 and fromthe secondary reservoir through the conduit 34 and pipe 40 into the port38.

The triple valve is further provided with an exhaust passage 41 whichwhen the valve is in running position as shown in Figure 1 communicateswith the conduit 36 to provide-a free exhaust from the brake cylinderthrough the passage 42 in the casing. \Vhen the valve is in the positionjust mentioned the port 44 therein is uncovered by the graduating valveJ and communicates with the conduit 34 for balancing the pressurebetween the primary and secondary auxiliary reservoirs. This port 44 isshown as a passage extending longitudinally of the valve but may beotherwise formed.

One of the important features of novelty embodied in this invention isthe improved construction of control valve for the piston 20. This valveis herein shown as cooperating with a pressure chamber K whichcommunicates by a port 45 with the conduit F for train line pressure,the chamber being provided with a perforated support 46 which limits themovement of the valve diaphragm 47 under different pressure conditions.This diaphragm may be supported in'position by an annular clamping ring48 and the valve casing 49 threaded into contact therewith. The casingis formed with a projected valve seat 50 through which a conduit 51extends to the head oi the easing. This head has a removable plug 81 forattaching a charging connection. Coop-erating with the seat is the valve52 which is formed with a yoke 53 by which it may be conveniently passedover the seat and applied in position. The yoke terminates in a foot 54adapted to Contact with the dialit) mea s is phragm 47 under movementthereof toward the left for the purpose of .actuating the valve. Thevalve is normally held in closed pasition by a spring which is tensionedrelative to the difference in pressure desired between the train lineand the auxiliary pressures, and this difference in pressure requiredfor operation of the valve may be adjusted to any desired degree bymeans of the threaded cap 56 which is provided with an aperture toreceive the valve stem 57 and contacts with the spring 55 so as to varyits tension.

For the purpose of introducing pressure from the secondary auxiliary tothe control valve chamber a conduit 58 extends from the conduit 8% andis provided at its: inlet to said chamber with a choke 59 to regulatethe pressure entering in the chamber. This conduit 58 may also beprovided with a till]- off cook 60. The conduit 51 from the controlvalve communicates with a pipe line 61 and at this pointa relief plug 62is provided and also a cut-off cook 82 for a purpose to be hereinafterdescribed in connection with the setting of the control valve.

The pipe 61 connects with a conduit 62 extending through the casing andcomment eating with a port 63 in the triple valve T. This port isdisposed to connect with a recess (i l in the graduating-valve J inorder to establish communication with a corresponding port 65 throughthe valve I and from which the conduit 66 extends to an inlet opening-(57 at one side of the control piston 20, that is at the left sidethereof when the parts are in forcible release position shown in Figure3.

The triple valve is provided with an exhaust port es adapted tocommunicate with an exhaust passage 69 in the casing to exhaust from theport 65 and conduit 66 when the parts are inserviceposition as shown inFigure 2. The cylinder A of the triple piston is provided with-a feedgroove 70 at one end thereof adapted to permit the pasage of the trainpipe pressure over the triple piston when in running position so as tofeed any overcharge to the primary auxiliary reservoir. The controlcylinder D is provided with a vent 71 which is made of such area thatthe escape of air from this cylinder is relatively slow and causessufficient compression between the control piston and partition-toregulate the speed of the forcible release and prevent a sudden orjamming action thereof.

The two auxiliaries may be separately arranged but are preferablyconstructed as a unit, each chamber being of substantially the samecapacity and separated from the other chamber by a partition 72. In theinitial use of the brake the reservoirs will be charged from the trainline pressure entering the primary reservoir and passing sure in therespective reservoirs.

therefrom by a pipe 73. into the governor 7-1 which is formed with apartition 7 5 carrying a cut off valve 76 which is normally held inclosed position by a spring 77 of sufficient tension to determine thedifference in pres The secondary reservoir is connected with thisgovernor above the diaphragm by the pipe 78. If this spring be set toexert a pressure of fifteen pounds for holding the valve closed anypressure in excess thereof from the primary reservoir will raise thevalve and flow into the secondary until the pressure therein inconnection with the spring tension causes the valve to close. Under theconditions described there would be a difference of fifteen poundspressure between the primary and secondary reservoirs.

in the illustration of this invention only such ports and connectionshave been shown are necessary to disclose the functions and operation ofthe present invention and it will be understood that further ports anddetails common to the standard triple valve me .hanism may be used inconnection withthe parts herein shown.

The general operation of the forcible release will be understood fromthe foregoing description and my prior patent bearing upon such anoperation and it will be seen that the overcharge at the'head end of thetrain, while effecting a release of the rear brakes thereon will bereceived by the primary auxiliary so that only little reduction inpressure in the train line is necessary to release simultaneously thebrakes of a long train whereby the rear brakes are not affected by theslow rise of the train line pressure as the release of each triplevalveis positively and forcibly effected.

Referring to the specific operation of this construction under serviceconditions, reference is made to Figure 1 where the parts are in runningor charging position and the air from the train line passes to thecylinder of the triple piston forcing the latter toward the right untilthe pressure passes through the feed groove to the auxiliary G. At thesame time the train line pressure passes from the port to the chamber Kof the control valve and bears upon the right face of the diaphragmtherein.

The feed of train line pressure from the auxiliary chamber l3 passesthrough the port 4A to the conduit 34 and thence to the sec0ndaryauxiliary tl'ircugh the pipe 33. The lower end of the port 441-. isformed with a port i l of approximately the area of feed groove 70 and areduced port 44, Figure 7, of substantially one half the size of theuniform recharge feed groove by the bushing of the triple piston so thatwhen making v a release all of the triple valves on the head end of thetrain that have three pounds or more in train line pressure above thatof 'ltil) the auxiliary G will be forced to a retarded release positionof the triple valve, thus compressing the spring bumper and moving thetriple valve to the right which shifts the reduced extended port 44 ofport 44 into connection with the conduit 34 so that pressure can slowlypass therethrough from the primary to the secondary auxiliary while inthis retarded position. In running position the port 44 feeds toauxiliary H, and in retarded position reduced port 44 feeds thereto,thus permitting a higher pressure or overcharge in auxiliary G above H,in a ratio of live to four pounds.

In the first service movement of the triple piston the port 44 is closedby the graduating valve J, as shown in Figure 2, and the pressure maynot pass from the primary to the secondary auxiliary as the slide valvetravels to service position. As soon as the triple piston returns torelease position the port 44 is uncovered by the graduating valve and asthis port passes over the conduit 34 in the seat the primary andsecondary auxiliaries will equalize in pressure. lVhile these ports passover the large opening in port 44 and onto the reduced port 44 thereinwhich is one half of the size of the feed groove over the triple piston,the air will continue to flow from the primary to the secondaryauxiliary until both are charged up to train line pressure and the partsare in the position shown in Figure 1.

As the auxiliary reservoirs are charged, air passes from the conduit 34through the conduit 58 to the control valve chamber on the auxiliaryside of the diaphragm 47 therein and this chamber is therefore alwayssubjected to the auxiliary pressure. This valve chamber is connectedwith the port 67 of the control piston cylinder by the conduits 62 and66 cooperating with the ports in the slide and graduating valves butthese ports are out of connection when in the release, running orcharging position as shown in Figure 1.

lVhen a reduction is made in the train line pressure the pressure in thetriple piston cylinder is reduced below that of the auxiliary chamber sothat the latter pressure forces this piston to service position andlikewise the valves carried thereby until the lower end of the port 37connects with the conduit 36 leading to the brake cylinder as shown inFigure 2. This takes port 44 out of connection with port 34 and at thesame time connects port of the slide valve to the conduit 34 in the seatthrough the recess 39 in the graduating valve which connects the slidevalve ports 38 and 40. The port 38 communicates with the port 37 and inservice position the graduating valve uncovers the latter, permittingair from the a xiliary chamber B to flow to the brake cylinder conduit36 and at the same time a pressure is applied through the conduit 34 andpipe 33 from the auxiliary secondary. This arrangement effects areduction in both of the auxiliaries relative to the reduction ofpressure in the train line and the pressure upon the brake cylinder.Vhen in this service position the chamber K of the con trol valve is atall times in communication with the train line pressure so that afterthe triple piston passes to a service lap position as shown in Figure 3,the pressures in both auxiliaries and in the respective piston and valvechambers are near equalization, the primary and secondary auxiliariesand the control valve chamber having only sufficient pressure to lap thetriple piston and graduating valve.

The spring of the control valve is set at the desired tension, forinstance three pounds, by the regulating nut, which holds this valveupon its seat in service lap position while the ports in the slide valvecon trolling the pressure to the piston 20 are in communication. Thepressure, however, cannot flow past the control valve because thepressures in the chamber K and control valve chamber are nearequalization and the spring being set at a differential of three poundsholds the control valve upon its seat where it will remain until thetrain line pressure is raised three pounds or more above that from thesecondary auxiliary which communicates with the control valve. When thisincrease in train line pressure occurs the movement to the left of thediaphragm by the increased pressure at that side opens the valve 52permitting a flow of pressure through the connections above described tothe control piston. At this time there is no pressure to the right ofthis pistonin its cylinder D and the movement of the control pistonunder the auxiliary pressure forces the small piston 24 against thepressure in chamber 17, which is train line pressure and brings its stem22 into contact with the triple piston forcing the same toward the rightor to release and running position.

During the releasing movement of the triple valve the port 68 thereof isbrought into communication with the exhaust passage 69 so that thepressure in the conduit 66 is relieved from the control piston and thetrain pipe pressure in the chamber G acts Hill upon the smaller piston24 to restore the control piston to its running position as in Figure 1.

In the continued release movement of the triple valve the graduatingvalve opens port 44 which is brought into communication with the conduit34 and the pressure in the two auxiliary reservoirs is permitted toequalize. It will thus be seen that if the triple valve mentioned is onthe head end of the train when the release is effected the rise of thetrain pipe pressure to three pounds iii or more over the auxiliarypressure will cause the triple valve to be forced to release positionthus cutting out the connection therefrom to the secondary auxiliary andpermitting the priniary auxiliary to over charge and triple piston toretain its released position at which time the graduating valve does notconnect the ports 63 and and the pressure in the secondary auxiliary andcontrol valve chamber is more than three pounds lower than that in thetrain pipe. Under such condition air cannot pass to the control pistonuntil the pressure from the primary auxiliary acts upon the brakecylinder and returns the part to lap position when the brake pipepressure is then approximately seven pounds higher than the secondaryauxiliary and control valve chamber. As the train pipe pressure is thehighest at the position just described the diaphragm re leases thecontrol valve to permit the flow of air to the control piston whichforcibly operates the triple piston to release. At this time the port 44and the conduit 34; connects the auxiliaries so that the pressuretherein equalizes and is consequently lower than the t *ain linepressure so that the triple valve will remain in release position.

When the parts are in emergency position the triple valve ports are inthe service position shown in Figure 2 and a release thereof is effectedby an increase in train line pressure of three pounds or more asheretofore described. In such emergency position the conduit 34 isopened by the slide valve and pressure from the secondary auxiliaryflows into the auxiliary chamber B while the valve also opens theemergency port 83 to permit both auxiliary pressures to act upon theemergency piston and brake cylinder. The disposition of this en'iergencyport relative to the conduit 34: is shown in Figure 8.

The governor connection between the auxiliaries is only necessary foruse when a car is first coupled or the triple valve first placed inoperation, at which time there is no pressure in the auxiliaryreservoir. The application of train line pressure at this time willforce the triple valve to release position and owing to the portarrangement the seconeary auxiliary would not receive pressure until thetrain line and primary auxiliary equalize. The use of the governorpermits the secondary auxiliary to be brought under pressure as soon asthe parts are in coupled relation. The construction of the control valveadapts the parts to be readily disconnected when necessary for repair orother purposes and the adjustment of the spring tension thereonregulates the difference in pressure necessary to secure an operation ofthe valve from the excess in the train line pressure. The adjustment ofthis spring tension may be effected in various manners, for instance thut-off cock 60 may e os nd the triple valve charged to say seventypounds pressure when the plug 62 is removed and a gauge applied to theplug connection with the valve casing.

The valve chamber may be charged tirough the connection 81 by an airline to sixty-seven pounds, or three pounds below that in the trainline. The plug 62 has a small vent suflicient to permit only a limitedescape of air and the regulating nut is then adjusted until the airceases to flow from the plug or vent 62. The difference between the twopressures is thus overcome by the spring and the control valve forced toits seat so that pressure cannot pass therethrough until there is anincrease in the train line over the auxiliary pressurewithin the valvecase. After this adjustment the cock 60 is again opened to permitcommunication with the secondary auxiliary reservoir. This cock may alsobe used to cut out the forcible release operation when desired but it isalso preferable to insert a similar cut-off cook 82 in the pipe 61 inorder to prevent any pressure action upon the diaphragm which wouldstrain or injure the same.

Vi i-en the triple piston is in forcible release position as shown inFigure?) and an emergency application of the brakes is made, a quickreduction in train line pressure results and the primary auxiliarypressure being much greater than the former acts against the controlpiston so that the triple piston will move toward the train line sideconnecting the port 65 with the exhaust .port 68 in order to exhaustpressure from the control piston chamber and effect a quick return ofthe parts toward the left or re-. lease position.

The inlet port 59 to the control valve chamber is provided with a chokeof such size that when the valve is raised from its seat by the greaterpressure upon the train line side of the diaphragm the pressure willpass from the valve chamber to the piston cylinder faster than thepressure from the secondary auxiliary can flow to the valve chamberthrough this choke. This results in letting the pressure in the valvechamber drop about ten pounds and any little reduction that may occur inthe train line at the same that the valve is open will not permit thevalve to close and stop the flow to the control piston before the triplepiston is forced to its release position. The continued flow of pressurefrom the secondary auxiliary through this choke will later charge thevalve chamber up to the auxiliary pressure but ample time is providedfor the complete releasing action before this occurs. In theillustration of the invention in Figures 1, 2 and 3 the port arrangementof the triple valve has been diagrammatically shown while the specificconstruction thereof is disclosed in Figures 4 to 8.

In the service position of the parts the primary auxiliary is connectedto the brake cylinder through the valve port 37 and conduit 36 while thesecondary auxiliary is similarly connected through the pipe 33 andconduit 34: which through the valve port 40 and recess in the slidevalve establishes communication with the auxiliary chamber, thusapplying pressure from both auxiliary reservoirs simultaneously at thesame rate that would be secured by a single service port in the standardconstruction.

It will be seen that tlns construction provides an efficient andaccurately operating construction of triple valve mechanism which is ofparticular importance when the feed valve supplying the train line iserratic in its operation as it only requires a slight increase in thetrain line pressure to operate the forcible release as it issupplemented in the operation of the mechanical device by the auxiliarypressure as before described. This prevents the sticking of the brakeswith the resultant heating of the wheels and forms a very valuableadjunct in connection with the so-called bridge braking in which thetriple pistons will not frequently release upon a slow rise of the trainline pressure and retain their hold, resulting in very unsatisfactoryoperation.

Brief statement of operation.

lVith the triple piston in running posi tion and the brakes released asshown in Figure 1, the train line pressure has dis posed the piston inalignment with the feed groove through which pressure from the trainline passes to first charge both auxiliaries and subsequently overchargethe primary auxiliary with a pressure which is later utilized inshifting the piston to service position. At this time the brake cylinderis in exhaust communication by the conduit 36 and 41 while the controlvalve chamber is in constant communication with the secondaryauxiliaryconduit 34 and the' train line and auxiliary pressures aresubstantially equalized so that the parts are retained in brake releaseposition. The triple valve ports 63 and are cut off and no pressurereaches the control piston which has previously been restored to itsrelease position by the train line pressure acting upon the valvecarried by its stem.

Upon reduction of the train line pressure the auxiliary pressure andovercharge moves the triple piston to service or braking position asshown in Figure 2. The pressure from both auxiliaries acts to move thetriple piston toward the left and this movement first shifts thegraduating valve to close port 44 and open port 37 communicating withthe brake cylinder. Further movement of the valve brings the port 4-0over the conduit 3% for the secondary auxiliary and also port 37 overthe brake cyl-- inder conduit 36 while the graduating valve connects theports 4-0 and 37 by its recess 39 and the port 38. Both auxiliaries arethus connected to the brake cylinder. The port 63 for the control pistonremains closed but port 65 therefrom is open to exhaust by the recess 64and ports 68 and 69, the train line pressure having been reduced. bclowthe auxiliary pressure and the tension upon the control valve so thatthe latter remains closed.

Upon the initial increase of train line pressure to effect forciblerelease of the brakes the parts assume the position shown in Figure 3with the train line pressure acting upon the triple piston and also uponthe diaphragm of the control valve to open the latter. The triple valveat this period cuts off the secondary auxiliary reservoir from thechamber B and establishes auxiliary pressure upon the control piston byconnecting parts 63 and 65, the control valve 52 now being opened by asubstantially three pound increase in train line pressure. The controlpiston is thus moved. to bring its stein into contact with the triplepiston to forcibly release the same in conjunction with the train linepressure thereon which requires the minimum of the latter pressure toeffect a release. Continued movement of the triple piston brings theparts to the release or running position shown in Figure 1, during whichexhaust is established from the control piston cylinder and this pistonrestored to release position by the train line pressure.

lVhile the details of this construction have been specifically shown anddescribed, the invention is not confined thereto as changes andalterations may be made therein without departing from the spiritthereof as defined by the following claims.

Having thus des0ibed my invention. what I claim as new and desire tosecure by Letters Patent is:

1. A triple valve mechanism comprising a main valve and its associatedtriple pirton, a triple piston cylind r, means for s .p plying trainline pressure to said cylinder. and auxiliary pressure reservoirconnected to actuate said piston to service position, mechanical meansfor forcing said piston to release position, and a secondary auxiliaryreservoir connected to operate said mechanical means.

2. A triple valve mechanism comprising main valve and its associatedtriple piston, a triple piston cylinder means for supplying train linepressure to said cylinder, an auxiliary pressure reservoir connected toactuate said piston to service position, me chanical means for forcingsaid piston to release position, and means for automatically applyingpressure supplemental to the train line pressureto-actuate saidmechanical release :means.

3. A triple valve mechanism comprising a main valve and its associatedtriple pieton, a triple :piston cylinder, means for supplying train linepressure to said, cylinder, a pressure reservoir and a secondaryauxiliary reservoir connected to actuate said piston to serviceposition, mechanical means for forcing said piston to release position,and means controlled by the main valve for establishing equalizedpressures in each auxiliary reservoir.

4. A triple valve mechanism comprising a main valve and its associatedtriple pis ton, a triple piston cylinder, means for supplying train linepressure to said cylinder, an auxiliary pressurereservoir connected toactuate said piston to service position, mechanical means for forcingsaid piston to release position, means for supplying an auxiliarypressure to operate said mechanical means, and a control valve for saidauxiliary pressure operably responsive to the predominating pressures. V

5. A triple valve mechanism comprising a main valve and its associatedtriple pis ton, a triple piston cylinder, means for supplying train linepressure to said cylinder, an auxiliary pressure reservoir connected toactuate said piston to service position, me chanical means for forcingsaid piston to release position, means for supplying an. auxiliarypressure to operate said mechanical means, and a control valve normallyclosed under spring tension and operable to open under excess of trainline pressure to admit auxiliary pressure to the forcible release means.

6. in a triple valve mechanism, a triple piston, a cylinder thereforprovided With a by-pass around said piston at a position traversed inits release travel, an auxiliary air chamber communicating with saidbypass, and a plurality of auxiliary reservoirs adapted to be connectedto said chamber for supply therefrom.

7 In a triple valve mechanism, a triple piston, a cylinder thereforprovided with a by-pass around said piston at a position traversed inits release travel, an auxiliary air chamber communicating With saidbypass, a plurality of auxiliary reservoirs connected for supply fromsaid chamber, and a valve controlled by said piston for permitting anovercharge of one reservoir relative to the other.

8. In a triple valve mechanism, a triple piston, a cylinder thereforprovided With a by-pass around said piston at a position traversed inits release travel, an auxiliary air chamber communicating with said bypass, a plurality of auxiliary reservoirs connected for supply from Saidchamber, and

a valve controlled by said piston for permitting an overcharge of onereservoir relative to the other and a subsequentequalization of thepressures in said reservoirs.

9. A triple valve mechanism including a triple piston carrying a mainvalve, a train line connection for moving said piston to releaseposition, mechanical means for forcibly initiating such movement, and aplurality of auxiliary reservoirs connected through the main valveduring its travel to equalize each other, or to apply pressure to abrake cylinder, or the forcible release means.

10. A triple valve mechanism including a triple piston carrying a mainvalve, a train line connection for moving said piston to releaseposition, mechanical means forforcibly initiating such movement, aplurality of auxiliary reservoirs connected through the main valve toequalize each other, or to apply pressure to a brake cylinder, or theforcible release means, and a control valve for the pressure line tosaid release adapted to apply pressure thereto upon a slight excess oftrain line pressure.

11. A triple valve mechanism embodying a triple piston subjected totrain line pressure and auxiliary reservoir pressure, mechanical meansfor shifting said piston to brake release position, and a pressureconnection from said reservoir supplemental to the train line pressurefor actuating said me chanical means.

12. A triple valve mechanism embodying a triple piston subjected totrain line pressure and auxiliary reservoir pressure, mechanical meansfor shifting said piston to brake release position, a control valve forapplying pressure to said mechanical means, and an; actuating member forsaid valve exposed to train line and auxiliary pressures.

13. A triple valve mechanism embodying a triple piston subjected totrain line pressure and auxiliary reservoir pressure, mechanical meansfor shifting said piston to brake release position, a control valve forapplying pressure to said mechanical means, and a diaphragm located in achamber connected to train line pressure and adapted upon excess thereofto open said valve.

14. A triple valve mechanism embodying a triple piston and valve carriedthereby, means to subject said piston to train line pressure andauxiliary reservoir pressure, mechanical means for shifting said pistonto brake release position, a control valve for said mechanical means,means for supplying auxiliary pressure to the chamber of said controlvalve, a conduit from said control valve to a triple valve port, aconduit from said port to the mechanical shifting means, and agraduating valve constructed to connect said ports during a releasingtravel of the triple piston.

15. A triple valve mechanism embodying a triple piston and valvecarriedthereby, means to subject said piston to train line pressure andauxiliary reservoir pressure, mechanical means for shiftingsaid pistonto brake release position, a control valve for said mechanical means,means for supplying auxiliary pressure to the chamber of said controlvalve, a conduit from said control valve to a triple valve port, conduitfrom said port to the mechanical shifting means, and a graduating valveconstructed to connect said ports during a releasing travel of thetriple piston and to exhaust from one of said ports in a travel of thetriple valve to service position.

16. A triple valve mechanism embodying a triple piston having a valve,means for applying train line pressure thereto, means for applying anauxiliary pressure to said piston comprising a plurality of auxiliaryreservoirs, and a graduating valve associated With the triple valve tocontrol the ports thereof and establish communication between saidreservoirs to equalize the pressure therein with the train line pressurewhen the triple piston is in brake releasing position.

17. A triple valve mechanism having a triple piston, means forsubjecting the same to train line pressure, primary and secondaryauxiliary reservoirs, the former being connected for direct applicationto said piston, a conduit leading from the secondary auxiliary, a triplevalve having ports communicating with said conduit and the auxiliarypressure from the primary reservoir, and a graduating valve associatedwith the triple valve for controlling said ports.

18. A triple valve mechanism having a triple piston, means forsubjecting the same to train line pressure, primary and secondaryauxiliary reservoirs, the former being connected for direct applicationto said piston, a conduit leading from the secondary auxiliary, a triplevalve having ports communicating with said conduit and the auxiliarypressure from the primary reservoir, a graduating valve associated withthe triple valve for controlling said ports, and a brake cylinder havinga conduit communicating with ports in said triple valve disposed toestablish communicating between both auxiliary reservoirs and the brakecylinder.

19. A triple valve mechanism having a triple piston, means forsubjecting the same to train line pressure, primary and'secondaryauxiliary reservoirs, the former being connected for direct applicationto said piston, a conduit leading from the secondary auxiliary, a triplevalve having ports communicating with said conduit and the auxiliarypressure from the primary reservoir, a graduating valve associated withthe triple valve for controlling said ports, and a brake cylinder havinga conduit communicating with ports in said triple'valve disposed toestablish communication between both auxiliary reservoirs and the brakecylinder, said triple valve being provided with a port connection forthe brake cylinder conduit to exhaust therefrom when the triple pistonis in brake release position.

20. In a triple valve mechanism, a triple piston, a train lineconnection thereto, an auxiliary reservoir pressure for actuating saidpiston, a forcible release device disposed to actuate said pistonthrough auxiliary pressure, a control valve and chamber for saidpressure, train line actuated means for opening said control valve,means for maintaining a constant auxiliary pressure in said valvechamber, and connections from said chamber to apply said auxiliarypressure to the forcible releasing means.

21. A triple valve mechanism embodying a triple piston, means forsubjecting the same to train line pressure and auxiliary reservoirpressure, means for forcibly releasing said triple valve, a controlvalve and chamber in communication with said auxiliary pressure,actuating means for said valve connected to the train line pressure, anadjustable spring tension for closing said control valve against thetrain line pressure, and a conduit from said valve to the forciblerelease means.

22. In a triple valve mechanism, a control valve comprising a yokecarrying a valve member and disposed. over a valve seat, means forpositively shifting said yoke and valve for actuating said valve in itsopening movement, and for tensioning said valve in closed position andadjusting the tension thereon.

23. In a triple valve mechanism, a control valve comprising a yokecarrying a valve member movable therewith and disposed over a valveseat, a diaphragm for actuating said valve in its opening movement,mechanical means for tensioning said valve in closed position, and afoot extended from said yoke and adapted to contact with said actuatingmeans to bodily shift the yoke and valve.

24:. In a triple valve mechanism, a casing provided with a chamber incommunication with a train line conduit, a diaphragm mounted in saidchamber, a support disposed therein for preventing excessive movement ofthe diaphragm in one direction, a control valve casing disposed at theopposite side of said diaphragm and formed with a projected valve seat,a valve mounted upon said seat and disposed to contact With thediaphragm in its movement in one direction, and connections from saidvalve seat to actuate a triple piston.

25. In a triple valve mechanism, a casing provided with a chamber incommunication with a train line conduit, a diaphragm mounted in saidchamber, .a support dis posed therein for preventing vexcessive movementofithe diaphragm in one direc tion, a control valve casing disposed atthe opposite side of said diaphragm andsformed with a projected valveseat, a valve mounted upon said seatand disposed to contact with thediaphragm in its movement in one direction, connections from said valveseat to actuate a triple piston, an auxiliary reservoir, a conduitextending therefrom to said valve chamber, and a choke disposed at theoutlet from said conduit to admit a less volume of pressure to thechamber than that discharged through the control valve.

26. In a triple valve mechanism, a control valve chamber, a controlvalve therein normally held in closed position under predeterminedtension, connections from said valve to means for actuating a triplepiston, means for opening said valve against the tension thereofcommunicating with the train line pressure, an auxiliary reservoirhaving a conduit leading to said control chamber, and a choke device atthe delivery from said conduit to effect a less supply of pressurethereto than that discharged through the control valve.

27. In a triple valve mechanism, a plurality of auxiliary reservoirs incommunication with the ports of said valve, said ports beingproportioned to effect an equal delivcry from each of the auxiliarycylinders to a brake cylinder. I

28. In a triple valve mechanism, a triple piston and cylinder thereforhaving a feed passage, a plurality of auxiliary reservoirs communicatingtherewith, a triple valve ported to prevent feed to one chamber whilethe other is overcharging, and to subsequently connect said chambers toequalize the pressure therein in the brake releasing travel of thetriple piston.

29. In a triple valve mechanism, a triple piston and cylinder thereforhaving a feed passage, a plurality of auxiliary reservoirs communicatingtherewith, a triple valve ported to prevent feed to one chamber whilethe other is overcharging and to subsequently connect said chambers toequalize the pressure therein in the brake releasing travel of thetriple piston, and subsequently to apply the pressure from bothauxiliaries to a brake cylinder connection when said triple piston is inservice position.

30. In a triple valve mechanism, a triple piston, a triple valve carriedthereby and provided with a. plurality of ports, a primary auxiliaryreservoir communicating with the ports of said valve, a secondaryauxiliary reservoir communicating with one of said ports, a brakecylinder having a conduit communicating with another of said ports, anda graduating valve actuated by the piston and cooperating with the portsof the triple valve to establish communication between the same.

31. In a triple valve mechanism, a triple piston, a triple valve carriedtherebysand provided with a plurality ofiports, a .primary auxiliaryreservoir communicating with the portsiof said/valve, a secondaryauxiliary reservoir communicating with one of said ports, a brakecylinder having a conduit communicating with another of said ports, acontrol piston disposed to forcibly release the triple piston, auxiliarypressure connections to the cylinder of said control piston disposed tocooperate with ports in said triple valve, and a graduating valveactuated by the triple piston and provided with a plurality of recessesto cooperate with the reservoir, brake cylinder, and control pistonports therein.

32. In a triple valve mechanism, a triple piston, a triple valve carriedthereby and provided with a plurality of ports, a primary auxiliaryreservoir communicating with the ports of said valve, a second auxiliaryreservoir communicating with one of said ports, a brake cylinder havinga con duit communicating with another of said ports, a control pistondisposed to forcibly release the triple piston, auxiliary pressureconnections to the cylinder of said control piston disposed to cooperatewith ports in said triple valve, and a graduating valve actuated by thetriple piston and provided with a plurality of recesses to cooperatewith the reservoir, brake cylinder, and control piston ports therein,said triple valve being further provided with an exhaust port for thecontrol piston disposed to cooperate with the graduating valve.

83. In a triple valve mechanism, a triple piston provided with a triplevalve and graduating valve, a casing formed with a pressure chamber andwith a train line conduit of decreasing capacity communicating with saidchamber and the triple piston, a control piston for said triple piston,a control valve disposed in communication with the chamber within saidcasing and connected to actuate said control piston, and an auxiliaryreservoir connected to said control valve. r

34. In a triple valve mechanism, a triple piston provided with a tri levalve and graduating valve, a casing ormed with a pressure chamber andwith a train line conduit of decreasing capacity communicating with saidchamber and the triple piston, a control piston for said triple piston,a control valve disposed in communication with the chamber within saidcasing and'connected to actuate said control piston, an auxiliaryreservoir connected to said control valve, a brake cylinder, and aconduit extending therefrom to said triple valve and decreasing in areaas it approaches the emergency piston having a'conduit adapted same. tobe opened in the" service position of said 10 35. In a triple valvemechanism, a triple piston, said main valve and graduating piston andmain valve carried thereby, a valve being ported to apply the pressureof 5 graduating valve cooperating with the main both auxiliaries to theemergency piston.

valve and actuated by said piston, a plu- I In testimony whereof I affixmy signature. rality of auxiliary reservoirs adapted to communicate Withsaid main valve, and an WALTER F. ATWOOD.

